Senators on Wednesday again blocked President Barack Obama’s pick of Caitlin J. Halligan to serve on an influential District of Columbia court amid accusations she supports an anti-gun agenda.

The target of a GOP filibuster in 2011, Halligan had already drawn objections over Second Amendment issues, and the mercurial congressional climate on gun rights that has prevailed since the Sandy Hook Elementary School shootings served only to heighten the controversy.

The Senate voted 51-41 to end debate on the nomination, nine votes shy of the 60 needed to move forward. Alaska’s Lisa Murkowski was the only Republican to cross party lines, voting to invoke cloture. She did the same in 2011. Last month, Lindsey Graham of South Carolina was the only GOP member of the Senate Judiciary Committee who did not oppose Halligan, opting to abstain from the panel’s vote. He voted “no” on the floor Wednesday.

Halligan was nominated to serve on the U.S. Court of Appeals for the District of Columbia Circuit. A former solicitor general for the state of New York, Halligan is general counsel in the Manhattan district attorney’s office. She was first nominated in 2010 to fill the seat vacated by U.S. Supreme Court Chief Justice John G. Roberts Jr.

Obama said in a statement Wednesday that he was “deeply disappointed” by the vote, adding that a majority of senators feel Halligan “is exactly the kind of person who should serve on this court.”

Republicans say Halligan is an activist judge and complain about her take on such issues as detainee policy, abortion and immigration. Americans United for Life has said it will score Halligan’s cloture vote because of her role in a case on anti-abortion protesters.

Judiciary panel member Orrin G. Hatch, R-Utah, on Tuesday called Halligan “one of the most activist judicial nominees that we’ve seen in years.”

“The Senate owes the president no deference [on such a pick],” Hatch said.

GOP senators, along with gun rights groups, object to Halligan’s backing of a legal argument stating that firearms manufacturers should be held liable for gun crimes committed by third parties. Critics have dismissed the legal position as a political ploy to undermine gun sales.

“As New York’s solicitor general, Halligan was one of the chief lawyers responsible for New York’s baseless and politically motivated efforts to bankrupt gun manufacturers using frivolous litigation,” wrote Gun Owners of America, calling Halligan “one of the most anti-gun judicial nominees in recent memory.”

On Wednesday, Senate GOP leaders circulated an email highlighting the view of the GOA and other critics. The National Rifle Association has opposed Halligan, and the conservative Committee for Justice is scoring the vote, too, calling her “uber-controversial” and “a committed opponent of gun rights.”

Minority Leader Mitch McConnell, R-Ky., said Wednesday that Halligan has “put [her] activist view into practice time and time again,” calling her take a “textbook example of judicial activism.”

Democrats maintained she was simply presenting the position of her client — the state of New York — and not her own personal views.

“She represented her client. That is what she was supposed to do,” said Maryland Democrat Benjamin L. Cardin. “That’s what a lawyer does.”

Assistant Majority Leader Richard J. Durbin, D-Ill., called the GOP critique “as empty as any argument I’ve ever heard on the floor of the Senate.”

D.C. Court Caseload

In 2011, GOP senators argued that the workload of the D.C. appellate court did not justify filling vacancies. They renewed that critique on Tuesday, with Hatch and fellow Utah Republican Mike Lee both citing falling case numbers.

But Judiciary Chairman Patrick J. Leahy of Vermont and other Democrats noted the court’s vacancies have doubled during the past two years, with four of 11 slots now empty.

Majority Leader Harry Reid, D-Nev., added, “Obama is the only president in the 65-year history of the D.C. Circuit Court not to have a single judge confirmed [to the court] during his first term.”

White House Press Secretary Jay Carney also weighed in, telling reporters at a news briefing Tuesday, “The court has never been this understaffed in its history.”

The D.C. appellate court is widely viewed as the second most powerful U.S. court, behind only the Supreme Court.

On Wednesday, Durbin and New York Democrat Charles E. Schumer cited the influential nature of the court as the core reason for GOP opposition to Obama’s pick.